1. Field of the Invention
The invention relates to surgical instruments and methods. More particularly, the invention relates to methods and apparatus for the minimally invasive treatment of gastric ulcers using a cautery device, although it is not limited thereto.
2. State of the Art
Minimally invasive (also known as endoscopic) surgery is not a new technology. However, it is only in recent years that such surgery has become so widely accepted that it is used in many diverse procedures. Minimally invasive surgery typically involves the making of a small incision (5–10 mm) in the vicinity of the surgical site, the installation of a port through the incision, and the extension of an endoscope through the port to the surgical site. Alternatively, an endoscope is sometimes lubricated and inserted through a body cavity such as the rectum or esophagus.
Gastrointestinal bleeding is a somewhat common and serious condition that can be fatal if left untreated. This problem has prompted the development of a number of endoscopic therapeutic approaches to achieve hemostasis, such as the injection of sclerosing agents, the attachment of mechanical hemostatic devices and contact electrocautery techniques. Mechanical hemostatic devices are typically in the form of clamps, clips, staples, sutures, etc. which are able to apply sufficient constrictive forces to blood vessels so as to limit or interrupt blood flow. Such devices are disclosed in U.S. Pat. No. 6,001,110. Electrocautery techniques involve the use of either monopolar or bipolar electrodes which are contacted to ulcerous tissue. A well known electrocautery device is disclosed in U.S. Pat. No. 5,336,222.
The known clip techniques and cautery techniques are only adequate for relatively small ulcers because the clips and/or cautery probes must be delivered through the working lumen of an endoscope. In addition to optical elements which carry fiber optics to illuminate the surgical site and which deliver an image from the surgical site, the endoscope typically has two or three lumena: one or two lumen(a) for aspiration and irrigation, and one (the working lumen) through which a surgical tool may be passed. The working lumen is typically very small in size (e.g., about 3 mm in diameter), and thus the size of the tools which may be used with a typical endoscope are severely limited in size.
Bleeding gastric ulcer lesions are not limited in size and are frequently too large to be effectively treated with the known mechanical and electrical techniques.